Light burst transmission/reception control system, parent station device used in the same, child station device, and light burst transmission/reception control method

ABSTRACT

A host station apparatus ( 10 ) generates band allocation information including identifications of slave station apparatuses ( 20 - 1  through  200 -n) and types of data to be transmitted by the slave station apparatuses and posts the information to the plural slave station apparatuses ( 20 - 1  through  20 -n). The plural slave station apparatuses ( 20 - 1  through  20 -n) identify as to whether or not the band allocation information is band allocation information about the data types of the slave station apparatuses respectively, and when the band allocation information is band allocation information about the data types of the slave station apparatuses, they control to transmit data to the host station apparatus ( 10 ) according to the data types represented by the band allocation information.

TECHNICAL FIELD

[0001] The present invention relates to an optical bursttransmission/reception control system where a plurality of slave stationapparatuses commonly use a transmission medium and a transmission band,a host apparatus posts band allocation information for controllingallocation of use transmission bands of the respective slave stationapparatuses to the respective slave station apparatuses, and the slavestation apparatuses transmit data to the host station apparatus based onthe band allocation information posted from the host stationapparatuses, the host station apparatus and the slave station apparatusto be used in this system, and an optical burst transmission/receptioncontrol method.

BACKGROUND ART

[0002] Conventionally, as a system where a plurality of slave stationapparatuses commonly use a transmission medium and a transmission bandand the respective slave station apparatuses transmit data to a hoststation apparatus according to band control by the host stationapparatus, for example, an optical network having n-numbered ONUs(Optical Network Units) and one OLT (Optical Distribution Termination)shown in FIG. 5/G.983.1—Generic physical configuration of the OpticalDistribution Network of Recommendation G. 983. 1 (Broadband opticalaccess systems based on Passive Optical Networks (PON) 1998/10) isknown.

[0003]FIG. 7 is a block diagram showing a schematic structure of theabove-mentioned optical network. In FIG. 7, OLT is a host stationapparatus, and a plurality of ONUs are slave station apparatuses.Moreover, ODN (Optical Distribution Network) is a transmission mediumcomposed of an optical fiber, an optical multiplexer/branching filterand the like. FIG. 8 is a diagram showing formats of data in a directionfrom OLT side to ONU side (downstream) and data in a direction from ONUside to OLT side (upstream) shown in ITU-T Recommendation FIG. 11/G.983. 1—Frame format for 155.52/155.52 Mbit/s PON. As shown in FIG. 8,the downstream data are composed of a fixed length cell of 53 bytes, andthe upstream data are composed of a fixed length cell of 56 bytes. Thedownstream data are multiple-addressed from one OLT to all ONUs, and asfor the upstream data, data transmission to one ONU is allowed to betransmitted by OLT for each time slot of each cell.

[0004] The permission of the data transmission for each upstream timeslot, namely, the post of the band allocation information is defined bythe format of the downstream data, and is inserted into a monitor andcontrol (PLOAM: Physical Layer Operations Administration andMaintenance) cell which is transmitted in a cycle of 28 cells. This bandallocation information is inserted as each byte of “GRANT 1” through“GRANT 27” of PLOAM cell as described in Table 8/G. 983. 1—Payloadcontent of downstream PLOAM cell of ITU-T Recommendation. As shown inFIG. 8, since the upstream data exist in 53 slots for each frame, “GRANT1” through “GRANT 27” which are inserted in the first PLOAM cell in thedownstream frame show band allocation information for the first through27th time slots in the upstream frame, and “GRANT 1” through “GRANT 27”which are inserted in the second PLOAM cell in the downstream frame showband allocation information for the 28th through 53rd time slots in theupstream frame. Namely, the allocation to the 53 time slots in theupstream frame is instructed by “GRANT 1” through “GRANT 27” which areinserted in the two PLOAM cells in the downstream frame.

[0005] The format of “GRANT” is shown in Table 10/G. 983.1—Specification of the grants in ITU-T Recommendation. In “Table”, atype of “GRANT” allocated to use of the upstream slots of ONUs is“DataGRANT” or “PLOAMGRANT”. “PLOAMGRANT” is allocated to transmissionof PLOAM cell in the upstream direction, and for allocation fortransmission of normal data, “Data GRANT” is used. A value to be used in“Data GRANT” is arbitrary except for partial reserved values. Values of“Data GRANT” to be previously used by respective ONUs as well as valuesof “PLOAM GRANT” are posted to the respective ONUs from OLT by messagesincluded in the downstream PLOAM cells in order that the respective ONUsthemselves recognize the band allocation. The formats of the messagesare shown in Grant allocation message in Downstream message formatsITU-T Recommendation, 8.3.8.2.1. One of these messages is transmitted toONU, and a value of “Data GRANT” and a value of “PLOAM GRANT” to be usedby this ONU are shown. The ONU receives this message and stores thevalue as initial setting, and as a result, in the case where stored“GRANT” exists in “GRANT 1” through “GRANT 27” in the PLOAM cellstransmitted from OLT, the ONU recognizes that band allocation of theupstream time slot exists for the ONU itself.

[0006] In such a manner, OLT sets “Data GRANT” and “PLOAM” which areindividual values for the respective ONUs, and before the respectiveONUs transmit upstream data, they transmit messages so as to manage theband allocation for the respective ONU in the upstream slots. ONU doesnot transmit data in a slot where band allocation to this ONU does notexist so as to prevent conflict of data in an upstream transmissionline.

[0007] Incidentally, in the optical network, since a type of datatransmitted by ONU cannot be discriminated, services stored in ONUcannot be occasionally satisfied sufficiently. For example, in the casewhere periodic data such as sound data which require periodictransmission upon real-time request and burst data which are transmittedin a burst manner such as file transmission between computers coexist,it is occasionally difficult to hold the periodic transmission of theperiodic data such as sound data securely.

[0008] With reference to FIGS. 9 and 10, there will be explained belowthe case where the periodic transmission of the periodic data becomesdifficult. FIG. 9 is a block diagram showing a structure of aconventional optical burst transmission/reception system, and FIG. 10 isa time chart showing a data transmission state in the case where ONU(slave station apparatus) stores a service which requires datatransmission of the periodic data and a service which requires datatransmission of the burst data.

[0009] In FIG. 9, a host station apparatus 10 is connected to aplurality of slave station apparatuses 20-1 through 20-n via a mainfiber 31, an optical splitter 30 and branch fibers 32-1 through 32-n.The optical splitter 30 branches an optical signal from the host stationapparatus 10 and transmits the branched signals to the slave stationapparatuses 20-1 through 20-n, and multiplexes the optical signals fromthe slave station apparatuses 20-1 through 20-n and transmits themultiplexed signal to the host station apparatus 10.

[0010] Firstly the host station apparatus 10 has a code allocationsection 14, and the code allocation section 14 previously sets codes asvalues of “GRANT” for the respective slave station apparatuses 20-1through 20-n, and transmits the values of “GRANT” to a management signaltransmission section 12. The management signal transmission section 12allows the input values of “GRANT” to be contained in a PLOAM cell(management signal) in a format that the values can be identified by theslave station apparatuses 20-1 through 20-n, and transmits themanagement signal to an optical transmitter-receiver 11. Here, as for acorresponding relationship between the slave station apparatuses 20-1through 20-n and the values of “GRANT”, sets of preset identificationnumbers of the slave station apparatuses 20-1 through 20-n and thevalues of “GRANT” are posted from the host station apparatus 10 to theslave station apparatuses 20-1 through 20-n respectively.

[0011] The optical transmitter-receiver 11 converts the managementsignal into an optical signal, and transmit the optical signal to theoptical splitter 30 via main fiber 31. The optical splitter 30distributes the optical signal via the branch fibers 32-1 through 32-nso as to transmit it to the slave station apparatuses 20-1 through 20-n.Respective optical transmitter-receivers 21 in the slave stationapparatuses 20-1 through 20-n convert input optical signals intoelectrical signals, and transmit them to at least code identificationsections 22 and allocation identification sections 23. The codeidentification section 22 fetches a management signal from the inputelectrical signal, and fetches the identification number preset in itsslave station apparatus and a value of “GRANT” relating to thisidentification number and stores them.

[0012] Thereafter, the band allocation section 13 of the host stationapparatus 10 transmits the values of “GRANT” presets for the slavestation apparatuses 20-1 through 20-n to the management signaltransmission section 12 with frequency according to bands required bythe slave station apparatuses 20-1 through 20-n, and the managementsignal transmission section 12 inserts the values of “GRANT” into theslot allocation areas in the upstream direction in the managementsignal, and multiple-addresses the management signal to the slavestation apparatuses 20-1 through 20-n via the opticaltransmitter-receiver 11. In the case where the band allocation is large,a lot of areas containing codes (values of GRANT) of the slave stationapparatuses with large band allocation appear in the slot allocationareas in the upstream direction, and in the case where the bandallocation is small, areas containing codes of the slave stationapparatuses with small band allocation are less in the slot allocationareas in the upstream direction. Namely, an interval of appearance ofthe codes allocated to the slave station apparatuses change due to theband allocation. The band allocation is posted from the host stationapparatus 10 to the slave station apparatuses 20-1 through 20-nrepeatedly.

[0013] The code identification sections 22 of the slave stationapparatuses 20-1 through 20-n detect the values of “GRANT” in themanagement signal and posts them to data reading sections 24. The datareading sections 24 check the values in the allocation areas in therespective slot input from the allocation identification sections 23,and when the values match with the codes posted from the codeidentification sections 22, the data reading sections 24 execute datareading process on the upstream time slots corresponding to the matchedslots. This data reading process attempts to read the data from a buffermemory 25 a, and when there exist no data to be read, the process readsdata from a buffer memory 25 b. The read data are multiplexed by amultiplexing section 27, and are transmitted to the data reading section24. The data reading section 24 transmits the multiplexed data to theoptical transmitter-receiver 21, and transmits them to the host stationapparatus 10 via the branch fibers 32-1 through 32-n, the opticalsplitter 30 and the main fiber 31. When there exist no data to be readin the buffer memories 25 a nor 25 b, the data reading section 24generates empty data so as to transmit them to the opticaltransmitter-receiver 21.

[0014] The data to be input into the buffer memory 25 a of the slavestation apparatus 20-1 are periodic data 26 a, and the data to be inputinto the buffer memory 25 b are burst data 26 b.The data reading section24 makes control so as to read the periodic data 26 a in the buffermemory 25 a in preference to the burst data 26 b in the buffer memory 25b. This is because the burst data to be input in the burst manner do notnormally require real-time property unlike sound data, and even iftransmission is delayed to a certain extent, all of the burst data maybe transmitted, but as the periodic data require real-time property, itis necessary that the periodic data have periodicity and are transmittedin a state that a delay is reduced as much as possible.

[0015] There will be explained below the data reading process in thecase where the periodic data 26 a (“a1” through “a4”) shown in FIG.10(a) and the burst data 26 b (“b1” through “b4”) shown in FIG. 10(b)are input respectively into the buffer memories 25 a and 25 b. The datareading section 24 reads the data from the buffer memories 25 a and 25 bwith an interval equivalent to a sum of the bands required fortransmission of the periodic data and the burst data (interval of datareading signals shown in FIG. 10(c)) correspondingly to the codesidentified by the allocation identifying section 23 (band allocationinformation) . In this case, since the periodic data 26 a are read inpreference to the burst data 26 b, as shown in FIG. 10(d), the readdata, which are read by the data reading section 24 and are transmittedto the optical transmitter-receiver 21, are read with an interval equalwith or double interval of a data reading signal shown in FIG. 10(c). Asa result, the transmission interval of the periodic data 26 a is notperiodic. For example, the periodic data “a4” deviate from theperiodicity.

[0016] In order to solve this problem, the band allocation section 13 ofthe host station apparatus 10 generates values of “GRANT” with the sameperiod as the periodic data and additionally generates values of “GRANT”for the burst data in the burst manner, and the slave station apparatus20-1 transmits their multiplexed result to the host station apparatus(see FIG. 11). In this case, the periodicity of the periodic data “a1”through “a4” is maintained. Particularly in the case where timedifference between the periodic data to be input into the buffer memory25 a and “GRANT” generated for the periodic data, namely time differencebetween the periodic data and the data reading signal is small, theperiodic data “a1” through “a4” transmitted from the slave stationapparatus 20-1 keep the periodicity.

[0017] However, as shown in FIG. 12, the in the case where timedifference between the periodic data input into the buffer memory 25 aand the data reading signal is large, at the time of the reading bymeans of the data reading signal corresponding to “GRANT” allocated forthe burst data, the input periodic data exist and they are readpreferentially. For this reason, there arises a problem that theperiodicity of the periodic data is not ipso facto maintained unlike theperiodic data “a2” (see period Tv1 and period Tv2 in FIG. 12).

[0018] The difference between the system shown in FIG. 11 and the systemshown in FIG. 12 is only a time relationship between the periodic datainput into the slave station apparatus 20-1 and the value of “GRANT”generated from the host station apparatus 10 (data reading signal) . Inthis case, the host station apparatus 10 can recognize a slot intervalTc required for electric transfer of the periodic data, but difficultlyrecognizes timing at which the periodic data are input into the slavestation apparatus 20-1. This is because the transmission time of theperiodic data capable of being recognized by the host station apparatus10 is only a slot position allocated by the host station apparatus 10originally. For this reason, it is difficult to securely avoid collapseof the periodicity of the periodic data shown in FIG. 11.

[0019] Here, there considers a system which once stores data whoseperiodicity is collapsed into a buffer memory and reads periodic datafrom this buffer memory periodically so as to compensate theperiodicity. However, in this case, there arises a problem thattransmission delay due to the storage of the periodic data occurs andthe original characteristic of the periodic data which requiresreal-time property cannot be kept securely.

[0020] Therefore, it is an object of the present invention to provide anoptical burst transmission/reception control system in which in the casewhere periodic data and burst data are multiplexed so as to betransmitted from one slave station apparatus to a host stationapparatus, periodicity of the periodic data is maintained and delay ofthe periodic data can be suppressed minimally, a host station apparatusand a slave station apparatus to be used in the system, and an opticalburst transmission/reception control method.

DISCLOSURE OF THE INVENTION

[0021] In the optical burst transmission/reception control systemaccording to one aspect of the present invention comprises a pluralityof slave station apparatuses which commonly use a transmission mediumand a transmission band, and a host station apparatus posts bandallocation information for controlling allocation of use transmissionbands of the slave station apparatuses to the slave station apparatuses.The respective slave station apparatuses transmit data to the hoststation apparatus based on the band allocation information posted fromthe host station apparatus. The host station apparatus has a bandallocation control unit which generates the band allocation informationincluding identifications of the slave station apparatuses and types ofdata to be transmitted by the slave station apparatuses and posting theinformation to the plurality of slave station apparatuses. The pluralityof slave station apparatuses have a data transmission control whichidentifies as to whether or not the band allocation information is bandallocation information about the data types of their slave stationapparatuses, and when the band allocation information is the bandallocation information about the data types of their slave stationapparatuses, making control so as to transmit data to the host stationapparatus according to the data types represented by the band allocationinformation.

[0022] According to this invention, the band allocation control unit ofthe host station apparatus generates the band allocation informationincluding identifications of the slave station apparatuses and types ofdata to be transmitted by the slave station apparatuses, and posts theinformation to the plural slave station apparatuses, and the datatransmission control unit of the plural slave station apparatusesidentify as to whether or not the band allocation information is bandallocation information for the types of data in their slave stationapparatuses, and when the band allocation information is the bandallocation information for the types of data in their slave stationapparatuses, the data transmission control unit controls itself totransmit data to the host station apparatus according to the types ofdata represented by the band allocation information.

[0023] In the above-mentioned optical burst transmission/receptioncontrol system, the host station apparatus allows the band allocationinformation to be included in a management information cell so as topost it to the respective slave station apparatuses.

[0024] Thus, the host station apparatus posts the band allocationinformation included in the management information cell to the slavestation apparatuses.

[0025] In the above-mentioned optical burst transmission/receptioncontrol system, the band allocation information is use authorizinginformation of time slots defined in a transmission direction from theslave station apparatuses to the host station apparatus.

[0026] Thus, the band allocation information is time slot useauthorizing information defined in the transmission direction from theslave station apparatuses to the host station apparatus.

[0027] In the above-mentioned optical burst transmission/receptioncontrol system, the data types are types of fixed-speed data whichrequire a real-time property and should be transmitted with constantperiod and burst data which are generated by transmission requestintermittently or temporarily.

[0028] Thus, the data types are classified into the fixed-speed dada,which requires the real-time property and should be transmitted withconstant period, and the burst data which are generated by transmissionrequest intermittently or temporarily.

[0029] In the above-mentioned optical burst transmission/receptioncontrol system, the host station apparatus further has a band changerequest detection unit which detects intermittent or temporal generationof band change request; and the band allocation control unit, as initialsetting, allocates a band to fixed-speed data to be transmitted withconstant period, and when the band change request detection unit detectsband change request, the band allocation unit allocates a band to burstdata which are newly generated intermittently or temporarily.

[0030] Thus, the band request detection unit of the host stationapparatus detects generation of the intermittent or temporary bandchange request, and as initial setting the band allocation control unitallocates a band to the fixed-speed data to be transmitted with constantperiod, and in the case where the band request detection unit detectsthe band change request, the band allocation control unit allocates aband to the burst data which are newly generated intermittently ortemporarily.

[0031] In the above-mentioned optical burst transmission/receptioncontrol system, the slave station apparatuses further have a bandrequest unit which, when burst data are generated by transmissionrequest intermittently or temporarily, requests the host stationapparatus to allocate a band to the burst data.

[0032] Thus, when burst data are generated by the transmission requestintermittently or temporarily the band request unit of the slave stationapparatus request the host station apparatus to allocate a band to theburst data.

[0033] In the above-mentioned optical burst transmission/receptioncontrol system, the band allocation information is information aboutgrouped plural data types;

[0034] the band allocation control unit presets information, whichrepresents a band ratio of the grouped plural data types, in the bandallocation information; and the data transmission control unitidentifies as to whether or not the band allocation information is bandallocation information about grouped data types of their slave stationapparatuses, and when the band allocation information is the bandallocation information about the grouped data types of the slave stationapparatuses, transmits data of the grouped plural types represented bythe band allocation information according to the band ratio.

[0035] Thus, the band allocation information is information about aplurality of data types divided into groups, and the band allocationcontrol unit presets information representing a band ratio between thegrouped plural data types in the band allocation information, and thedata transmission control unit identifies as to whether or not the bandallocation information is band allocation information about the groupeddata types of the slave station apparatus. When the band allocationinformation is the band allocation information about the grouped datatype of the slave station apparatus, the data transmission control unittransmits the data of the grouped plural data types represented by theband allocation information according to the band ratio.

[0036] In the above-mentioned optical burst transmission/receptioncontrol system, when the band allocation control unit controls bandallocation for a slave station apparatus which does not identify a typeof data to be transmitted, the band allocation control unit posts bandidentification information including identification of the slave stationapparatus to the slave station apparatus, and when the band allocationcontrol unit controls band allocation for a slave station apparatuswhich identify a type of data to be transmitted, the band allocationcontrol unit posts band allocation information including theidentification of the slave station apparatus and the data type to theslave station apparatus.

[0037] Thus, when the band allocation control unit controls bandallocation for a slave station apparatus which does not identify a typeof data to be transmitted, the band allocation control unit posts bandidentification information including identification of the slave stationapparatus to the slave station apparatus. When the band allocationcontrol unit controls band allocation for a slave station apparatuswhich identify a type of data to be transmitted, the band allocationcontrol unit posts band allocation information including identificationof a slave station apparatus and the type of data to the slave stationapparatus. Further, the slave station apparatuses having variousstructures and functions coexist.

[0038] The host station apparatus according to another aspect of thepresent invention is used in an optical burst transmission/receptioncontrol system. This optical burst transmission/reception control systemincludes a plurality of slave station apparatuses which commonly use atransmission medium and a transmission band, and a host stationapparatus posts band allocation information for controlling allocationof use transmission bands of the slave station apparatuses to the slavestation apparatuses. The respective slave station apparatuses transmitdata to the host station apparatus based on the band allocationinformation posted from the host station apparatus. The host/devicecomprises a band allocation control unit which generates the bandallocation information including identifications of the slave stationapparatuses and types of data to be transmitted by the slave stationapparatuses, and posting the information to the plural slave stationapparatuses.

[0039] According to the above-mentioned aspect, the band allocationcontrol unit generates the band allocation information includingidentifications of the respective slave station apparatuses and types ofdata to be transmitted by the slave station apparatuses, and posts themto the plural slave station apparatuses.

[0040] The slave station apparatus according to still another aspect ofthe present invention is used in an optical burst transmission/receptioncontrol system. This optical burst transmission/reception control systemincludes a plurality of slave station apparatuses which commonly use atransmission medium and a transmission band, and a host stationapparatus posts band allocation information for controlling allocationof use transmission bands of the slave station apparatuses to the slavestation apparatuses. The respective slave station apparatuses transmitdata to the host station apparatus based on the band allocationinformation posted from the host station apparatus. The slave stationapparatus comprises a data transmission control unit which identifies asto whether or not the band allocation information is band allocationinformation about a data type of its slave station apparatus, and whenthe band allocation information is the band allocation information aboutthe data type of the slave station apparatus, making control so as totransmit data to the host station apparatus.

[0041] According to the above-mentioned aspect, the data transmissioncontrol unit identifies as to whether or not the band allocationinformation is band allocation information about data types of theirstation apparatus, and when the band allocation information is bandallocation information about the data type of the station apparatus, thedata transmission control unit makes control so as to transmit data tothe host station apparatus according to data types represented by theband allocation information.

[0042] The optical burst transmission/reception control method accordingto still another aspect of this invention is a method in which aplurality of slave station apparatuses commonly use a transmissionmedium and a transmission band, and a host station apparatus posts bandallocation information for controlling allocation of use transmissionbands of the slave station apparatuses to the slave station apparatuses,and the respective slave station apparatuses transmit data to the hoststation apparatus based on the band allocation information posted fromthe host station apparatus. The optical burst transmission/receptioncontrol method comprises the initial post step of previously posting theband allocation information including identifications of the slavestation apparatuses and types of data to be transmitted by the slavestation apparatuses from the host apparatus to the plurality of slavestation apparatuses; the holding step of holding the band allocationinformation posted at the initial post step by means of the slavestation apparatuses; the post step of posting the band allocationinformation including instruction of bands from the host stationapparatus to the slave station apparatuses; and data transmissioncontrol step of identifying as to whether or not the band allocationinformation posted at the post step is band allocation information aboutdata types of the slave station apparatuses respectively by means of theslave station apparatuses, and when the band allocation information isthe band allocation information about the data types of the slavestation apparatuses, making control to transmit data to the host stationapparatus according to the data types represented by the band allocationinformation.

[0043] According to the above-mentioned aspect, at the initial poststep, the host station apparatus previously posts the band allocationinformation including identifications of the slave station apparatusesand types of data to be transmitted by the slave station apparatuses tothe plural slave station apparatuses, and at the holding step the slavestation apparatuses hold the band allocation information posted at theinitial post step, and at the post step the host station apparatus poststhe band allocation information including band instruction to the slavestation apparatuses, and at the data transmission control step the slavestation apparatuses identify as to whether or not the band allocationinformation posted at the post step is their band allocation informationfor data types of the slave station apparatuses, and when the bandallocation information is band allocation information for the data typesof the slave station apparatuses, the slave station apparatuses makecontrol to transmit the data to the host station apparatus according tothe data types represented by the band allocation information. For thisreason, for example in the case where periodic data such as sound datawhich require the real-time property and have fixed periodicity, andburst data which are generated by transmission request intermittently ortemporarily exist one slave station apparatus, a band for the burst datais controlled separately from the periodic data.

[0044] In the above-mentioned optical burst transmission/receptioncontrol method, the band allocation information posted at the initialpost step and at the post step is information about a plurality ofgrouped data types.

[0045] Thus, the band allocation information which are posted by theinitial post step and the post step is information about plural groupeddata types.

[0046] The above-mentioned optical burst transmission/reception controlmethod further comprises the detection step of detecting as to whetheror not burst data are input into the slave station apparatuses by theslave station apparatuses; and the band request step of, when thedetection step detects the input of the burst data, transmitting bandrequest of the burst data to the host station apparatus, wherein whenthe host station apparatus detects the band request, the post step poststhe band request including the band allocation information about theburst data to the slave station apparatuses.

[0047] Thus, at the detection step the slave station apparatus detectsas to whether or not burst data are input into itself, and when thedetection step detects input of burst data, at the band request stepband request for the burst data is transmitted to the host stationapparatus, and when the host station apparatus detects the band request,at the post step the band allocation information for the burst data isincluded in the band request so as to be posted to the slave stationapparatus.

BRIEF DESCRIPTION OF THE DRAWINGS

[0048]FIG. 1 is a block diagram showing a structure of an optical bursttransmission/reception control system according to a first embodiment ofthe present invention;

[0049]FIG. 2 is a timing chart showing reading control of periodic dataand burst data in a slave station apparatus shown in FIG. 1;

[0050]FIG. 3 is a block diagram showing the optical bursttransmission/reception control system according to a second embodimentof the present invention;

[0051]FIG. 4 is a block diagram showing the optical bursttransmission/reception control system according to a third embodiment ofthe present invention;

[0052]FIG. 5 is a block diagram showing the optical bursttransmission/reception control system according to a fourth embodimentof the present invention;

[0053]FIG. 6 is a timing chart showing the reading control of periodicdata and burst data in a slave station apparatus shown in FIG. 5;

[0054]FIG. 7 is a block diagram showing a whole schematic structure of aconventional optical burst transmission/reception control system;

[0055]FIG. 8 is a diagram showing formats of upstream frame anddownstream frame;

[0056]FIG. 9 is a block diagram showing a structure of a conventionaloptical burst transmission/reception control system;

[0057]FIG. 10 is a timing chart showing reading control of periodic dataand burst data in a slave station apparatus shown in FIG. 9;

[0058]FIG. 11 is a timing chart showing another reading control of theperiodic data and burst data in the slave station apparatus shown inFIG. 9;

[0059]FIG. 12 is a timing chart showing one example of another readingcontrol of the periodic data and burst data in the slave stationapparatus shown in FIG. 9.

BEST MODE FOR CARRYING OUT THE INVENTION

[0060] Embodiments of the optical burst transmission/reception controlsystem, the host station apparatus and the slave station apparatus to beused in the system, and the optical burst transmission/reception controlmethod of the present invention will be explained below with referenceto the accompanying drawings.

First Embodiment

[0061]FIG. 1 is a block diagram showing a structure of the optical bursttransmission/reception control system according to the first embodimentof the present invention. In FIG. 1, in the optical bursttransmission/reception control system, a service management section 15is further provided in the optical burst transmission/reception controlsystem shown in FIG. 9, and a service identification section 29 isfurther provided in the slave station apparatuses 20-1 through 20-n.Moreover, instead of the data reading section 24 in the optical bursttransmission/reception control system shown in FIG. 9, data readingsections 24 a and 24 b for reading data from buffer memories 25 a and 25b are provided. A multiplexing section 28 is provided instead of themultiplexing section 27, and the multiplexing section 28 multiplexesdata read by the data reading sections 24 a and 24 b so as to transmitthem to an optical transmitter-receiver 21. The other parts of thestructure are the same as those in the optical bursttransmission/reception control system shown in FIG. 9, and the samereference numerals are given to the same parts of the structure.

[0062] In FIG. 1, the service management section 15 makes differentcodes as values of “GRANT” have one to one correspondence to respectivetypes of data input into the slave station apparatuses 20-1 through20-n, and transmits this correspondence information to a code allocationsection 14. The types of data are classified into periodic data andburst data. Similarly to the code allocation section 14 shown in FIG. 9,the code allocation section 14 transmits the code values to a managementsignal transmission section 12, and the management signal transmissionsection 12 transmits a management signal including this code values tothe slave station apparatuses 20-1 through 20-n via an opticaltransmitter-receiver 11, a main fiber 31, an optical splitter 30, branchfibers 32-1 through 32-n.

[0063] Similarly to the code identification section 22 shown in FIG. 9,the code identification sections 22 of the slave station apparatuses20-1 through 20-n fetch identification numbers which are preset in therespective slave station apparatuses and the code values (values ofGRANT) having one to one correspondence to the identification numbersand store them. As a result, data transmission control for therespective types of data from the slave station apparatuses 20-1 through20-n to the host station apparatus 10 is initialized. The serviceidentification sections 29 post the values of “GRANT” of periodic datato the data reading sections 24 a for reading periodic data, and postthe values of “GRANT” of burst data to the data reading sections 24 bfor reading burst data.

[0064] Thereafter, a band allocation section 13 of the host stationapparatus 10 inserts the values of “GRANT”, which are preset accordingto the types of data for the respective slave station apparatuses 20-1through 20-n, into upstream slot allocation areas in a down streammanagement signal with a frequency according to bands required byvarious data in the slave station apparatuses 20-1 through 20-n, andtransmits them to the management signal transmission section 12. Themanagement signal transmission section 12 transmits the managementsignal to the slave station apparatuses 20-1 through 20-n via theoptical transmitter-receiver 11, the main fiber 31, the optical splitterand the branch fibers 32-1 through 32-n.

[0065] Allocation identification section s23 of the slave stationapparatuses 20-1 through 20-n detect the values of “GRANT” in themanagement signal and posts them to the data reading sections 24 a and24 b. The data reading sections 24 a and 24 b check the values of theupstream slot allocation areas input from the allocation identificationsections 23, and when the values match with the code values (values ofGRANT) posted from the service identification sections 29, the datareading sections 24 a and 24 b try to read data from the buffer memories25 a and 25 b respectively with respect to upstream time slotscorresponding to the matched slots. When data exist, the data readingsections 24 a and 24 b transmit the read data to the multiplexingsections 28, and when data do not exist, they generate and transmitempty data to the multiplexing sections 28. The multiplexing sections 28multiplex the input data and transmit them to the opticaltransmitter-receivers 21, and transmits them to the host stationapparatus 10 via the branch fibers 32-1 through 32-n, the opticalsplitter 30 and the main fiber 31.

[0066] With reference to the timing chart shown in FIG. 2, there will beexplained below data output of periodic data “a1” through “a4” and burstdata “b1” through “b4” in the slave station apparatuses 20-1 through20-n. FIGS. 2(a) and 2(b) show the periodic data “a1” through “a4” andthe burst data “b1” through “b4”. FIG. 2(c) shows a periodic datareading signal, which corresponds to band allocation information for theperiodic data and represents timing at which the data reading sections24 a read periodic data 26 a (“a1” through “a4”) from the buffermemories 24 a. Moreover, FIG. 2(d) shows a burst data reading signal,which corresponds to band allocation information for the burst data andrepresents timing at which the data reading sections 24 b read burstdata 26 b (“b1” through “b4”) from the buffer memories 25 b. Further,FIG. 2(e) shows reading data which are read by the periodic data readingsignal and the burst data reading signal and are output from the datareading sections 24 a and 24 b.

[0067] The band allocation information detected by the allocationidentification sections 23 is input with an interval corresponding tobands required for the transmission of the periodic data and burst data,and the periodic data reading signal and the burst data reading signalshown in FIGS. 2(c) and 2(d) are generated according to the input. Thedata reading sections 24 a and 24 b read the periodic data “a1” through“a4” and the burst data “b1” through “b4” according to the periodic datareading signal and the burst data reading signal respectively. As aresult, the periodic data “a1” through “a4” are read with an interval ofthe slots allocated to the periodic data so as to be transmitted to thehost station apparatus 10, and thus periodicity of the periodic data ismaintained.

[0068] According to the first embodiment, the service management section15 of the host station apparatus 10 provides values of “GRANT” forrespective types of data to the slave station apparatuses 20-1 through20-n so as to control the bands, and the slave station apparatuses 20-1through 20-n read data for the respective types of the data. For thisreason, for example in the case where periodic data and burst data aretransmitted from one slave station, the data can be transmitted to thehost station apparatus 10 in a state that the periodicity is maintainedwithout deteriorating the periodicity of the periodic data.

Second Embodiment

[0069] A second embodiment of the present invention will be explainedbelow. In the first embodiment, all the slave station apparatuses 20-1through 20-n have the same structure, but in the second embodiment thesystem is constituted so that the slave station apparatuses 20-1 through20-n in the first embodiment and the slave station apparatuses 20-1through 20-n shown in FIG. 9 coexist.

[0070]FIG. 3 is a block diagram showing the structure of the opticalburst transmission/reception control system according to the secondembodiment of the present invention. In FIG. 3, as for the slave stationapparatuses 20-1 through 20-n, the slave station apparatuses having thestructure of the slave station apparatuses 20-1 through 20-n in thefirst embodiment and the slave station apparatuses having the structureof the slave station apparatuses 20-1 through 20-n shown in FIG. 9coexist as mentioned above. For example, the slave station apparatus20-1 has the same structure as that of the slave station apparatuses20-1 through 20-n in the first embodiment, and the slave stationapparatus 20-n has the same structure as that of the slave stationapparatuses 20-1 through 20-n shown in FIG. 9. The other parts of thestructure are the same as in the first embodiment and the same referencenumerals are given to the common parts of the structure.

[0071] Here, since the post of initial setting in the slave stationapparatuses 20-1 through 20-n from the host station apparatus 10 or thecontrol using band allocation information is carried out independentlyin the slave station apparatuses 20-1 through 20-n, the post and thecontrol between the host station apparatus 10 and the slave stationapparatus 20-1 are carried out similarly to the first embodiment, andthe post and the control between the host station apparatus 10 and theslave station apparatus 20-2 are carried out similarly to theconventional optical burst transmission/reception control system shownin FIG. 9.

[0072] According to the second embodiment, similarly to the firstembodiment, the periodicity of the periodic data can be maintained, andthe system can be constituted so that the conventional slave stationapparatus 20-2 coexists. For this reason, the flexible system can bestructured.

Third Embodiment

[0073] A third embodiment of the present invention will be explainedbelow. In the second embodiment the system where the slave stationapparatuses 20-1 through 20-n in the first embodiment and theconventional slave station apparatuses 20-1 through 20-n shown in FIG. 9coexist is structured, but in the third embodiment the system isstructured so that the internal structure of the slave stationapparatuses 20-1 through 20-n in the first embodiment is mixed with theinternal structure of the conventional slave station apparatuses 20-1through 20-n shown in FIG. 9.

[0074]FIG. 4 is a block diagram showing the structure of the opticalburst transmission/reception control system according to the thirdembodiment of the present invention. In FIG. 4, the slave stationapparatus 20-1 is provided with a data reading section 41, two buffermemories 42 a and 42 b and a multiplexing section 44 instead of the datareading section 24 b band the buffer memory 25 b in the secondembodiment. The data reading section 41, the two buffer memories 42 aand 42 b, and the multiplexing section 44 correspond to the data readingsection 24 and the two buffer memories 25 a and 25 b, and themultiplexing section 27 shown in FIG. 9. In FIG. 4, the slave stationapparatuses 20-1 through 20-n may have the same structure of the slavestructure 20-1, but in FIG. 4 the structure of the slave stationapparatus 20-2 is the same as the structure of the slave structureapparatuses 20-1 through 20-n shown in FIG. 9. Namely, the slave stationapparatuses 20-1 through 20-n shown in FIG. 9 coexist. The other partsof the structure are the same as in the second embodiment, and the samereference numerals are given to the common parts of the structure.

[0075] The service management section 15 of the host station apparatus10 makes codes values as values of “GRANT” correspond to type groups ofdata to be input into the slave station apparatus 20-1, and transmitsthe correspondence information and band ratio of the groups to the codeallocation section 14. For example, in the slave station apparatus 20-1,since periodic data are input into the buffer memory 25 a and two typesof burst data are input into the buffer memories 42 a and 42 brespectively, the service management section 15 sets the two types ofthe burst data “1” (43 a) and “2” (43 b) as one group, and makes onecode of a value of “GRANT” correspond to this group. Moreover, theservice management section 15 makes one type of periodic data correspondto one code of a value of “GRANT”. As a result, the service managementsection 15 makes the slave station apparatus 20-1 correspond to twodifferent values of “GRANT”. Further, a band ratio is set for the twotypes of burst data 43 a and 43 b. Here, the slave station apparatus20-2 is made to correspond to one value of “GRANT”. The information istransmitted to the management signal transmission section 12, and themanagement signal transmission section 12 inserts the information into amanagement signal so as to transmit it to the slave station apparatuses20-1 through 20-n.

[0076] The service identification section 29 of the slave stationapparatus 20-1 recognizes the value of “GRANT” set for the periodic data26 a, the values of “GRANT” set for the burst data 43 a and 43 b and theband ratio, and posts the value of “GRANT” set for the periodic data 26a to the data reading section 24 a, and posts the values of “GRANT” setfor the burst data 43 a and 43 b and the band ratio to the data readingsection 41.

[0077] Thereafter, the band allocation section 13 of the host stationapparatus 10 transmits the values of “GRANT”, which are preset for theperiodic data 26 a and the burst data 43a and 43 b in the slave stationapparatus 20-1, to the management signal transmission section 12according to a frequency corresponding to a band required by theperiodic data 26 a and a frequency corresponding to a total bandrequired by the burst data 43 a and 43 b in the slave station apparatus20-1. The management signal transmission section 12 inserts the inputvalues of “GRANT” into the upstream slot allocation areas in themanagement signal so as to transmit them to the slave station apparatus20-1. This management signal is similarly transmitted with a frequencycorresponding to a total sum of the bands required by the various datato be input into the slave station apparatuses 20-1 through 20-n. Thevalues of “GRANT” which are preset for the slave station apparatuses20-1 through 20-n are inserted into the upstream slot allocation areasin the management signal.

[0078] Meanwhile, the allocation identification section 23 of the slavestation apparatus 20-1 detects the values of “GRANT” in the managementsignal input from the host station apparatus 10, and posts the values of“GRANT” to the data reading sections 24 a and 24 b. The data readingsections 24 a and 24 b check the values of “GRANT” input from theallocation identification section 23, and when the values match with thecodes (values of GRANT) posted from the service identification section29, the data reading sections 24 a and 24 b attempt to read the data inthe buffer memories 25 a and 42 a correspondingly to upstream time slotscorresponding to the values of “GRANT” which are detected as the matchedvalues. When the data exist, the data reading sections 24 a and 24 btransmit the data to the multiplexing section 28, and when the data tobe read do not exist, they generate empty data so as to transmit them tothe multiplexing section 28.

[0079] At this time, the data reading section 41 controls a reading timeratio of the burst data 43 a in the buffer memory 42 a to the burst data43 b in the buffer memory 42 b based on the band ratio in the grouptransmitted from the service identification section 29. For example, inthe case where the band ratio of the burst data 43 a to the burst data43 b is 1:2, the first reading is executed for the buffer memory 42 aonce and for the buffer memory 42 b twice. In the case where data to beread do not exist in one buffer memory, the data reading section 41attempts to read from the other buffer memory. The read data aretransmitted to the multiplexing section 44 and are transmitted from thedata reading section 41 to the multiplexing section 28, but in the casewhere data to be read do not exist in the buffer memories 42 a and 42 b,the data reading section 41 generates empty data so as to transmit themto the multiplexing section 28.

[0080] The data, which were transmitted from the data reading sections24 a and 24 b and are multiplexed by the multiplexing section 28, aretransmitted to the host station apparatus 10 via the branch fibers 32-1through 32-n, the optical splitter 30 and the main fiber 31.

[0081] Since the post of the initial setting and the control using theband allocation information from the host station apparatus 10 to theslave station apparatuses 20-1 through 20-n are carried outindependently for the slave station apparatuses 20-1 through 20-n, thepost and the control between the host station apparatus 10 and the slavestation apparatus 20-1 are carried out according to the above-mentionedprocessing procedure, and the post and the control between the hoststation apparatus 10 and the slave station apparatus 20-2 are executedsimilarly to the conventional optical burst transmission/receptioncontrol system shown in FIG. 9.

[0082] The slave station apparatuses 20-1 through 20-n in the firstembodiment are connected as the slave station apparatuses in the fourthembodiment, and the slave station apparatuses in the first embodiment,the slave station apparatuses in the third embodiment and theconventional slave station apparatuses shown in FIG. 9 may coexist.

[0083] According to the third embodiment, even if the structure where aplurality of buffer memories are connected to one data reading section,the data stored in the plural buffer memories form groups, and one valueof “GRANT” is set for each of the groups, and the band ratio of the datain the group is set. For this reason, the band for the respective datain the group can be controlled collectively and flexibility of thestructure can be secured. Moreover, also in this case, similarly to thefirst and second embodiments, the periodicity of the periodic data isnot deteriorated.

Fourth Embodiment

[0084] A fourth embodiment of the present invention will be explainedbelow. In the first through third embodiments, the bands in the slavestation apparatuses 20-1 through 20 n are controlled based on the postof the band allocation information such as the values of “GRANT” fromthe host station apparatus 10, but in the fourth embodiment the bandsare requested from the slave station apparatuses 20-1 through 20-n, andthe host station apparatus 10 controls band allocation of the slavestation apparatuses 20-1 through 20-n based on the band request.

[0085]FIG. 5 is a block diagram showing a structure of the optical bursttransmission/reception system according to the fourth embodiment of thepresent invention. In FIG. 5, the slave station apparatus 20-1 through20-n are further provided with a management signal transmission section51 for transmitting a band change request included in a managementsignal, and the host station apparatus 10 is further provided with aband change request/unrequest monitor 16 for monitoring a band changerequest signal in the management signal. The other parts of thestructure are the same as in the first embodiment, and the samereference numerals are given to the common parts of the structure.

[0086] The service management section 15 of the host station apparatus10 makes codes as values of “GRANT correspond to types of data to beinput into the slave station apparatuses 20-1 through 20-n usingdifferent values for the respective slave station apparatuses 20-1through 20-n, and transmits the correspondence information to the codeallocation section 14. Further, the service management section 15 makescodes as values of “GRANT” for transmitting management signals from theslave station apparatuses 20-1 through 20-n correspond respectively tothe slave station apparatuses 20-1 through 20-n using different values,and transmits the information to the code allocation section 14. Thecode allocation section 14 transmits the code values to the managementsignal transmission section 12, and the management signal transmissionsection 12 transmits the corresponded code values as the managementsignals to the slave station apparatuses 20-1 through 20-n.

[0087] The service identification section 29 of the slave stationapparatus 20-1 recognizes the value of “GRANT” set for the periodic data26 a, the value of “GRANT” set for the burst data 26 b and the value of“GRANT” set for the management signal from the slave station apparatus20-1. The service identification section 29 posts the value of “GRANT”set for the periodic data 26 a to the data reading section 24 a, thevalue of “GRANT” set for the burst data 29 b to the data reading section24 b, and the value of “GRANT” set for the management signal to themanagement signal transmission section 51.

[0088] Thereafter, the band allocation section 13 of the host stationapparatus 10 transmits the values of “GRANT” which are preset for thevarious data and the management signals in the slave station apparatuses20-1 through 20-n to the management signal transmission section 12 witha frequency according to the preset bands of the data and the presetband of the management signals. The management signal transmissionsection 12 transmits the management signals into which the input valuesof “GRANT” are input into the upstream slot allocation areas to theslave station apparatuses 20-1 through 20-n. However, “0” as an initialvalue is set in the band for the burst data 26 b, and a value of “GRANT”is not allocated to the burst data 26 b.

[0089] In the slave station apparatus 20-1, in the case where the burstdata 26 b are input into the buffer memory 25 b and transmission of theburst data 26 b is required, the necessity of the data transmission isposted from the buffer memory 25 b to the management signal transmissionsection 51. In another way, the management signal transmission section51 monitors a stored stat of the burst data 26 b in the buffer memory 25b.

[0090] When the management signal transmission section 51 accepts thepost from the buffer memory 25 b, it waits until the preset value of“GRANT” of the management signal is input from the allocationidentification section 23, and when the value of “GRANT is input fromthe allocation identification section 23, the management signaltransmission section 51 transmits the upstream management signal inwhich the transmission request of the burst data 26 b is included to themultiplexing section 28 and transmits this management signal to the hoststation apparatus 10 via the optical transmitter-receiver 21.

[0091] The band change request/unrequest monitor 16 of the host stationapparatus s10 monitors this upstream management signal and detects thetransmission request of the burst data 26 b in the management signal.When this transmission request is detected, the band changerequest/unrequest monitor 16 posts the band change request to the bandallocation section 13. The band allocation section 13 allocates a bandto the burst data 26 b based on this band change request, and transmitsthe value of “GRANT” for the burst data 26 b to the management signaltransmission section 12 with a frequency according to the allocation.The management signal transmission section 12 inserts the value of“GRANT” into the upstream slot allocation areas in the downstreammanagement signal and transmits the downstream management signal to theslave station apparatus 20-1 via the optical transmitter-receiver 11. Asa result, the data reading section 24 b of the slave station apparatus20-1 reads the burst data 26 b in the buffer memory 25 b, and places theburst data 26 b on a specified time slot so as to transmit the data tothe host station apparatus 10.

[0092] The management signal transmission section 51 allows a storedamount, a transmission delay allowable amount or input time of the burstdata 26 b to be included in the upstream management signal so that asshown in FIG. 6(b) the band allocation section 13 can output the bandallocation information for the burst data in the burst manner. In thiscase, not the preset band but an actually necessary band can beallocated to the burst data 26 b, and thus a band of a transmission linecan be used efficiently.

[0093] In addition, since the post and the band control from the hoststation apparatus 10 to the slave station apparatuses 20-1 through 20-nare controlled independently in the slave station apparatuses 20-1through 20-n, the reading control of the periodic data 26 a in the slavestation apparatuses 20-1 through 20-n is the same as the reading controlof the periodic data 26 a in the slave station apparatuses 20-1 through20-n in the first embodiment. As a result, in the transmission ofperiodic data between the host station apparatus 10 and the slavestation apparatuses 20-1 through 20-n, the periodicity of periodic datacan be maintained.

[0094] Similarly to the second and third embodiments, slave stationapparatuses having another structure may be connected as the slavestation apparatuses 20-1 through 20-n and they may be coexist. Moreover,the band change request/unrequest monitor 17 may allocate bands based onnot only the transmission request from the upstream management signalbut also a band change request signal 17 input from an apparatusconnected to the host station apparatus 10.

[0095] According to the fourth embodiment, similarly to the firstthrough third embodiments, the periodicity of periodic data can bemaintained, and the transmission of burst data is requested from theslave station apparatuses 20-1 through 20-n, and a band which isactually required for the transmission of burst data is allocated basedon this transmission request. For this reason, a band of thetransmission line can be used efficiently.

[0096] As explained above, according to the present invention, a bandallocation control unit of the host station apparatus generates the bandallocation information including identifications of the slave stationapparatuses and types of data to be transmitted by the slave stationapparatuses, and posts the information to the plural slave stationapparatuses, and a data transmission control unit of the plural slavestation apparatuses identify as to whether or not the band allocationinformation is band allocation information for the types of data intheir slave station apparatuses, and when the band allocationinformation is the band allocation information for the types of data intheir slave station apparatuses, the data transmission control unitcontrols itself to transmit data to the host station apparatus accordingto the types of data represented by the band allocation information. Forthis reason, in the case where periodic data such as sound data havingconstant periodicity which requires the real-time property and burstdata which are generated by the transmission request intermittently ortemporarily exist in one slave station apparatus, the band control forthe burst data is made separately from the periodic data. For thisreason, the periodicity of the periodic data can be maintained securely,and a delay of transmission of the periodic data can be suppressedminimally.

[0097] Moreover, since the host station apparatus posts the bandallocation information which is included in a management informationcell to the respective slave station apparatuses, the band allocationinformation can be posted securely to the slave station apparatusessecurely.

[0098] Furthermore, since the band allocation information is useauthorizing information of time slots specified in the transmissiondirection from the slave station apparatus to the host stationapparatuses, the band control is realized easily only by specifying theupstream time slots, and the post and identification of the bandallocation information and the data transmission control in the slavestation apparatuses can be carried out easily and swiftly.

[0099] Moreover, since the data types are classified into fixed-speeddata which requires the real-time property and should be transmittedwith constant period and burst data which are generated by thetransmission request intermittently or temporarily, the periodicity ofthe fixed-speed data can be maintained and the burst data can betransmitted efficiently.

[0100] Furthermore, a band request detection unit of the host stationapparatus detects generation of an intermittent or temporary band changerequest, and as initial setting the band allocation control unitallocates a band to fixed-speed data to be transmitted with fixedperiod. When the band request detection unit detects the band changerequest, it allocates a band to burst data which are newly generatedintermittently or temporarily so that the transmission band can beallocated to burst data efficiently and flexibly.

[0101] Moreover, when burst data are generated by the transmissionrequest intermittently or temporarily, a band request unit of the slavestation apparatuses request the host station apparatus to allocate aband to the burst data so that only when transmission of the burst datais required, the burst data can be transmitted, and the transmissionbands can be used efficiently.

[0102] Furthermore, the band allocation information is information abouta plurality of data types divided into groups, and the band allocationcontrol unit presets information representing a band ratio between thegrouped plural data types in the band allocation information, and thedata transmission control unit identifies as to whether or not the bandallocation information is band allocation information about the groupeddata types of the slave station apparatus. When the band allocationinformation is the band allocation information about the grouped datatype of the slave station apparatus, the data transmission control unittransmits the data of the grouped plural data types represented by theband allocation information according to the band ratio, and thusflexible band control can be made easily.

[0103] Moreover, when the band allocation control unit controls bandallocation for a slave station apparatus which does not identify a typeof data to be transmitted, the band allocation control unit posts bandidentification information including identification of the slave stationapparatus to the slave station apparatus. In the case where the bandallocation control unit controls band allocation for a slave stationapparatus which does not identify a type of data to be transmitted, theband allocation control unit posts band allocation information includingidentification of a slave station apparatus and the type of data to theslave station apparatus. Further, slave station apparatuses havingvarious structures and functions coexist. As a result, the periodicityof periodic data is maintained and simultaneously the flexible systemcan be structured.

[0104] According to the next invention, a band allocation control unitgenerates the band allocation information including identifications ofrespective slave station apparatuses and types of data to be transmittedby the slave station apparatuses, and posts them to the plural slavestation apparatuses. For this reason, for example in the case whereperiodic data such as sound data which require real-time property andhave fixed periodicity, and burst data which are generated bytransmission request intermittently or temporarily exist in one slavestation apparatus, since a band for the burst data is controlledseparately from the periodic data, the periodicity of the periodic datacan be maintained securely, and a delay of transmission of the periodicdata can be suppressed minimally.

[0105] According to the next invention, a data transmission control unitidentifies as to whether or not the band allocation information is bandallocation information about data types of their station apparatus, andwhen the band allocation information is band allocation informationabout the data type of the station apparatus, the data transmissioncontrol unit makes control so as to transmit data to the host stationapparatus according to data types represented by the band allocationinformation. For this reason, for example in the case where periodicdata such as sound data which require the real-time property and havefixed periodicity, and burst data which are generated by transmissionrequest intermittently or temporarily exist one slave station apparatus,a band for the burst data is controlled separately from the periodicdata. For this reason, the periodicity of the periodic data can bemaintained securely, and a delay of transmission of the periodic datacan be suppressed minimally.

[0106] According to the next invention, at the initial post step, thehost station apparatus previously posts the band allocation informationincluding identifications of the slave station apparatuses and types ofdata to be transmitted by the slave station apparatuses to the pluralslave station apparatuses, and at the holding step the slave stationapparatuses hold the band allocation information posted at the initialpost step, and at the post step the host station apparatus posts theband allocation information including band instruction to the slavestation apparatuses, and at the data transmission control step the slavestation apparatuses identify as to whether or not the band allocationinformation posted at the post step is their band allocation informationfor data types of the slave station apparatuses, and when the bandallocation information is band allocation information for the data typesof the slave station apparatuses, the slave station apparatuses makecontrol to transmit the data to the host station apparatus according tothe data types represented by the band allocation information. For thisreason, for example in the case where periodic data such as sound datawhich require the real-time property and have fixed periodicity, andburst data which are generated by transmission request intermittently ortemporarily exist one slave station apparatus, a band for the burst datais controlled separately from the periodic data. For this reason, theperiodicity of the periodic data can be maintained securely, and a delayof transmission of the periodic data can be suppressed minimally.

[0107] Moreover, since the band allocation information which are postedby the initial post step and the post step is information about pluralgrouped data types, flexible band control can be made easily.

[0108] Furthermore, at the detection step the slave station apparatusdetects as to whether or not burst data are input into itself, and whenthe detection step detects input of burst data, at the band request stepband request for the burst data is transmitted to the host stationapparatus, and when the host station apparatus detects the band request,at the post step the band allocation information for the burst data isincluded in the band request so as to be posted to the slave stationapparatus. For this reason, only when transmission of the burst data isrequired, the burst data can be transmitted, and transmission bands canbe used efficiently.

Industrial Applicability

[0109] As mentioned above, the optical burst transmission/receptioncontrol system, the host station apparatus, the slave station apparatusand the optical burst transmission/reception control method used in thesystem of the present invention are suitable for a data transmissionsystem where a plurality of slave station apparatuses commonly use atransmission medium and a transmission band, the host station apparatusposts band allocation information for controlling allocation of the usetransmission bands of the slave station apparatuses to the slave stationapparatuses, and the slave station apparatuses transmit data to the hoststation apparatus based on the band allocation information posted fromthe host station apparatus.

1. An optical burst transmission/reception control system comprising: aplurality of slave station apparatuses which commonly use a transmissionmedium and a transmission band, and a host station apparatus which postsband allocation information for controlling allocation of usetransmission bands of said slave station apparatuses to said slavestation apparatuses, wherein said respective slave station apparatusestransmit data to said host station apparatus based on the bandallocation information posted from said host station apparatus, whereinsaid host station apparatus has a band allocation control unit whichgenerates the band allocation information including identifications ofsaid slave station apparatuses and types of data to be transmitted bysaid slave station apparatuses and posting the information to saidplurality of slave station apparatuses, and wherein said plurality ofslave station apparatuses have a data transmission control unit whichidentifies as to whether or not the band allocation information is bandallocation information about the data types of their slave stationapparatuses, and when the band allocation information is the bandallocation information about the data types of their slave stationapparatuses, making control so as to transmit data to said host stationapparatus according to the data types represented by the band allocationinformation.
 2. The optical burst transmission/reception control systemaccording to claim 1, wherein said host station apparatus allows theband allocation information to be included in a management informationcell so as to post it to said respective slave station apparatuses. 3.The optical burst transmission/reception control system according toclaim 1, wherein the band allocation information is use authorizinginformation of time slots defined in a transmission direction from saidslave station apparatuses to said host station apparatus.
 4. The opticalburst transmission/reception control system according to claim 1,wherein the data types are types of fixed-speed data which require areal-time property and should be transmitted with constant period andburst data which are generated by transmission request intermittently ortemporarily.
 5. The optical burst transmission/reception control systemaccording to claim 1, wherein said host station apparatus further has aband request detection unit which detects intermittent or temporalgeneration of band request, and wherein said band allocation controlunit, as initial setting, allocates a band to fixed-speed data to betransmitted with constant period, and when said band request detectionunit detects band request, said a band allocation unit allocates a bandto burst data which are newly generated intermittently or temporarily.6. The optical burst transmission/reception control system according toclaim 1, wherein said slave station apparatuses further have a bandrequest unit which, when burst data are generated by transmissionrequest intermittently or temporarily, requests said host stationapparatus to allocate a band to the burst data.
 7. The optical bursttransmission/reception control system according to claim 1, wherein theband allocation information is information about grouped plural datatypes, wherein said band allocation control unit presets information,which represents a band ratio of the grouped plural data types, in theband allocation information, and wherein said data transmission controlunit identifies as to whether or not the band allocation information isband allocation information about grouped data types of their slavestation apparatuses, and when the band allocation information is theband allocation information about the grouped data types of the slavestation apparatuses, transmits data of the grouped plural typesrepresented by the band allocation information according to the bandratio.
 8. The optical burst transmission/reception control systemaccording to claim 1, wherein when the band allocation control unitcontrols band allocation for a slave station apparatus which does notidentify a type of data to be transmitted, said band allocation controlunit posts band identification information including identification ofthe slave station apparatus to the slave station apparatus, and when theband allocation control unit controls band allocation for a slavestation apparatus which identify a type of data to be transmitted saidband allocation control unit posts band allocation information includingthe identification of the slave station apparatus and the data type tothe slave station apparatus.
 9. A host station apparatus used in anoptical burst transmission/reception control system that includes aplurality of slave station apparatuses which commonly use a transmissionmedium and a transmission band, and a host station apparatus which postsband allocation information for controlling allocation of usetransmission bands of said slave station apparatuses to said slavestation apparatuses, wherein said respective slave station apparatusestransmit data to said host station apparatus based on the bandallocation information posted from said host station apparatus, saidhost station apparatus comprises a band allocation control unit whichgenerates the band allocation information including identifications ofsaid slave station apparatuses and types of data to be transmitted bysaid slave station apparatuses, and posting the information to saidplural slave station apparatuses.
 10. A slave station apparatus used inan optical burst transmission/reception control system that includes aplurality of slave station apparatuses which commonly use a transmissionmedium and a transmission band, and a host station apparatus which postsband allocation information for controlling allocation of usetransmission bands of said slave station apparatuses to said slavestation apparatuses, wherein said respective slave station apparatusestransmit data to said host station apparatus based on the bandallocation information posted from said host station apparatus, saidslave station apparatus comprises a data transmission control unit whichidentifies as to whether or not the band allocation information is bandallocation information about a data type of its slave station apparatus,and when the band allocation information is the band allocationinformation about the data type of the slave station apparatus, makingcontrol so as to transmit data to said host station apparatus.
 11. Anoptical burst transmission/reception control method, in which aplurality of slave station apparatuses commonly use a transmissionmedium and a transmission band, and a host station apparatus posts bandallocation information for controlling allocation of use transmissionbands of said slave station apparatuses to said slave stationapparatuses, and said respective slave station apparatuses transmit datato said host station apparatus based on the band allocation informationposted from the host station apparatus, the method comprising: theinitial post step of previously posting the band allocation informationincluding identifications of said slave station apparatuses and types ofdata to be transmitted by said slave station apparatuses from said hostapparatus to said plurality of slave station apparatuses; the holdingstep of holding the band allocation information posted at the initialpost step by means of said slave station apparatuses; the post step ofposting the band allocation information including instruction of bandsfrom said host station apparatus to said slave station apparatuses; andthe data transmission control step of identifying as to whether or notthe band allocation information posted at the post step is bandallocation information about data types of said slave stationapparatuses respectively by means of said slave station apparatuses, andwhen the band allocation information is the band allocation informationabout the data types of said slave station apparatuses, making controlto transmit data to said host station apparatus according to the datatypes represented by the band allocation information.
 12. The opticalburst transmission/reception control method according to claim 11,wherein the band allocation information posted at the initial post stepand at the post step is information about a plurality of grouped datatypes.
 13. The optical burst transmission/reception control methodaccording to claim 11, further comprising: the detection step ofdetecting as to whether or not burst data are input into said slavestation apparatuses by said slave station apparatuses, and the bandrequest step of, when the detection step detects the input of the burstdata, transmitting band request of the burst data to said host stationapparatus, wherein when said host station apparatus detects the bandrequest, said post step posts the band request including the bandallocation information about the burst data to said slave stationapparatuses.